How it works
These quantities follow widely used catering rules of thumb: about two drinks per guest in the first hour and one per hour after that, 1 to 1.5 pounds of ice per guest, and about 6 ounces of main protein per person for a meal.
For appetizers, plan about 5 pieces per person before a meal. If appetizers are the meal, plan 10 or more pieces per person for the first two hours, and about 4 more per hour after.
A 750 ml bottle of wine pours five 5-ounce glasses, and a 750 ml bottle of liquor makes about sixteen 1.5-ounce drinks. Split the alcoholic drinks across wine, beer and cocktails however suits your crowd.
Formula
Drinks = guests × (2 + 1 per hour after the first)
Questions people ask
How many drinks per person for a party?
Plan on two in the first hour and one each hour after. A 4-hour party needs about 5 drinks per guest, counting both alcoholic and non-alcoholic.
How much ice do I need?
About 1 pound per guest for drinks, or 1.5 to 2 pounds in hot weather or if you are also chilling bottles in a cooler.
How many bottles of wine for 50 guests?
For a 3-hour party where most guests drink wine, about 40 bottles: 50 guests × 4 drinks ÷ 5 glasses per bottle.